When I put my 2.0 (4 w/D-Jet) together I didn't use the thick insulators, just some gasket that I had. The car seems to run fine but my manifolds do get hot. I've ordered some insulators from PP.
So hear are my questions.

Do I need to use gaskets with the insulators?

What are the cons of not running the insulators?

Thanks,

Lennie

The new insulators should come with gasket material already on both sides.........You should use the insulators with F.I. or Carbs.

without the insulators you will tend to over heat your injectors, which may fail , which may spew gas all over, the gas may ignite and then it is a moot point as yoru car will be bruned to a crisp. you will also shorten the life of the injecector seals then you get intake leaks

get them insulators installed!!!! there there for a reason. yes you need them and gaskets to seal it up well.

Thank you. They arrived today. I'll install them this weekend.
I did not order gaskets. Are you suggesting a gasket above and below each insulator? Totalling 4 gaskets?

The stock insulators come with a thin paper gasket on each side ...


Mr. Krusty is probably going to chew my head off, but i usually use a thin layer of gasket-goo on the paper.

Make sure you get the metal mating surfaces on the heads and intakes runners really clean. The last thing you want is a vacuum leak there ...
Andy

Use grease on intake manifold gaskets, seals up real good and you can take the gaskets off/on many times without ever ruining them.